Tom Cruise & Katie Holmes Marry!

It's official: Tom Cruise and Katie Holmes are now husband and wife. The couple exchanged vows Saturday in front of more than 150 guests at the Odescalchi Castle in Lake Bracciano, Italy, their rep, Arnold Robinson, confirms to PEOPLE.

"The wedding was absolutely beautiful," says a guest.

With thousands of fans, photographers and TV cameras watching from afar, Cruise and Holmes were joined by family – Katie's dad Martin walked her down the aisle – and a slew of celeb pals, including Will and Jada Pinkett Smith, Brooke Shields and Chris Henchy, Victoria Beckham, Jennifer Lopez and Marc Anthony, and Jim Carrey and Jenny McCarthy, among others.

More on Their Wedding

The sunset ceremony was performed by a Scientology minister, according to a statement from their reps. The wedding party included Cruise's children, Isabella and Connor, the best man was Cruise's best friend, David Miscavige – the head of the Church of Scientology – and Katie's sister Nancy Blaylock served as the matron of honor.

Though initially there were questions about whether Cruise and Holmes's marriage on Saturday was official – the Mayor of Bracciano, Italy, said the couple needed to have a civil ceremony in town in order to make it legal – Cruise's reps say Tom and Katie took care of everything beforehand.

"As is customary for couples marrying outside of the United States, Cruise and Holmes officialized their marriage in Los Angeles prior to their departure for Italy," according to the statement.

Other details released Saturday by the newlyweds:

 The bride: Holmes wore an off-the-shoulder Armani gown with an ivory silk train adorned in Valenciennes lace and Swarovski beaded crystal embroidery. She accessorized her gown with an ivory tulle floor-length veil and ivory silk shoes. Armani, which outfitted the entire wedding, also supplied Katie's bouquet of calla lilies, as well as a champagne evening gown, which she wore at the reception. (For more details on who wore what, see PEOPLE's related story.)

 The groom: Armani outfitted Cruise with a navy blue tuxedo from the Giorgio Armani Hand Made to Measure collection. The jacket label read, "Giorgio Armani for Tom Cruise."

 The couple's rings: Their rings were white gold Cartier with diamonds.

 The meal: After cocktails, guests were served Italian hors d'oeuvres, followed by a multi-course meal.

Saturday's wedding started on a damp note, with scattered rain throughout the morning. Holmes and 7-month-old daughter Suri were escorted into the castle under a cluster of green umbrellas. A little over an hour later, the groom was escorted from the Hassler hotel in Rome to Lake Bracciano 18 miles away. With the sun going down, candles lit up the perimeter of the 15th-century castle as limousines carrying the guests drove through the gates.

Fans and media were kept at a safe distance from the castle: Police checkpoints prevented anyone unauthorized from getting too close, and journalists were stationed in the nearby town square.

Saturday's ceremony brought the couple's 19-month romance full circle: Cruise and Holmes first stepped out as a couple in Rome in April 2005, with Cruise already referring to Holmes as "amore mio" just a few weeks after their first date (sushi, a private plane ride and a motorcycle trip to the beach).

Life changed even more in mid-June 2005. During a late-night candlelit dinner at the Eiffel Tower in Paris, Cruise proposed with a five-carat diamond ring. "I want to marry her as soon as possible," Cruise announced. "You have to do what you feel is right," he told PEOPLE at the time. "It's (about) your own integrity and how you want to live your life."

The pair had another reason to celebrate in October, when they announced they were expecting a baby. Holmes "almost seems born for motherhood," her pal and former Dawson's Creek costar Oliver Hudson told PEOPLE. "She's a nurturer."

The pair welcomed 7-lb., 7-oz. Suri on April 18. "The moment I looked in her eyes I felt like ... Mom," Holmes told the magazine of her new bundle of joy. "She's the miracle of our life."